xayacatl.

See an image that represents xayacatl in the Visual Lexicon of Aztec Hieroglyphs, ed. Stephanie Wood (Eugene, Ore.: Wired Humanities, 2020-present).

çan yayactzintli catca amo qualxayaque yhuan çan pitzahuactzintli catca amo nacayo = she was quite weak, had not a pretty face, was quite thin, was not fleshy. (central Mexico, early seventeenth century)
Codex Chimalpahin: Society and Politics in Mexico Tenochtitlan, Tlatelolco, Culhuacan, and Other Nahuatl Altepetl in Central Mexico; The Nahuatl and Spanish Annals and Accounts Collected and Recorded by don Domingo de San Antón Muñón Chimalpahin Quauhtlehuanitzin, eds. and transl. Arthur J. O. Anderson and Susan Schroeder (Norman: University of Oklahoma Press, 1997), vol. 1, 136–137.

yn achtopa oquimocopinilicah yn maestroz yn tlapallaCuiloque pintores amo yuhcatzintli omoquixti yn itlaÇoxayacatzin = The first time the master artisans, the painters, had made a copy of him, his precious face did not come out as a good likeness
Here in This Year: Seventeenth-Century Nahuatl Annals of the Tlaxcala-Puebla Valley, ed. and transl. Camilla Townsend, with an essay by James Lockhart (Stanford: Stanford University Press, 2010), 148–149.

toxayac titixtlaça = Our face: We turn away our face in disgust or rage (central Mexico, sixteenth century)
Fray Bernardino de Sahagún, Primeros Memoriales, ed. Thelma D. Sullivan, et al. (Norman: University of Oklahoma Press, 1997), 255.

xaiacatl = face (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1961), 112.

"2 Tecpatl 1520 ... yhquac yn mochintin quitocayotiaya teoçavatl cēca temahmauhti ynic mochiuh vey çavatl mochi quihtlaco yn texayac vel ic tlaixpoliovac quin ōcan peuhtica yn eztli yn tlayelli mihtoua Auh y ye nepa ayc mochiva oncā ocempeuh yn ixquich ica axcan valquiztiuh cocoliztli (f. 3v)" = "2 Flint-knife (year) 1520 ... It was when everyone called it God-pox. People were very frightened at how the great pox broke out. It spoiled everyone's faces; [the face was greatly harmed because of it? there was great loss of life because of it?]. Afterwards began what is called blood and filth (dysentery). And before that time it had never happened; from then began all of the epidemics that have broken out until now."
Frances Krug, "The Nahuatl Annals of the Tlaxcala-Puebla Region," ch. 4, pp. 44–45, Ph.D. Dissertation draft written in the 1980s, with transcriptions and translations approved by James Lockhart. Cited here by SW.

iniquac mocha in intlalnacayo pozahua, xayacacoztia, amiqui, ihuan ahuel maxixa, ahuel atl quinoquia = cuando toda la su carne terrestre (cuerpo) está hinchado se vuelve amarilla la cara tienen sed y no poder orinan no poder agua lo derraman (centro de México, s. XVIII)
Neville Stiles, Jeff Burnham, James Nauman, "Los concejos médicos del Dr. Bartolache sobre las pastillas de fierro: Un documento colonial en el náhuatl del siglo XVIII," Estudios de Cultural Náhuatl 19 (1989), 269–287, ver página 281.

auh in cuaxaiacatl caltech pilcaia quihualito: “Ca zan iuhqui o, yn atle noconitosnequi”. Nima motlato huehuento quicuitihuetzito cuauhxaiacatl, ythualco quihualmaiauh yc hualamotlac. Oncan i yntetzauh omochiuh çeiohual çemihuitl tlatilulca = y una máscara de madera que estaba colgada en la pared dijo: “Siendo así, yo no quiero decir nada”. Entonces corrió el viejecillo, cogió la máscara, y la azotó contra el suelo. Estos fueron los agüeros de los tlatelolcas de noche y de día. (Mexico City, c. 1572)
Ana Rita Valero de García Lascuráin and Rafael Tena, Códice Cozcatzin (México: Instituto Nacional de Antropología e Historia, Benemérita Universidad Autónoma de Puebla, 1994), 103.